Ms Nielsen said: "This leaflet was home published by a volunteer, not professionally published. It's clearly a mistake that is embarrassing to the person who made it, so we're not going to investigate further or name and shame.

"Our mayoral campaign relies heavily on volunteers and doesn't have the luxury of the big budget funding that some of the other candidates have, so I'm very grateful that supporters are contributing their time and effort in the Lib Dem fight back."